You're correct. The Trend Micro Mobile Security for iOS no longer have the App Scan feature. This is due to changes in iOS 9, the App Scan feature of Mobile Security for iOS is no longer supported. There are limitations that iOS 9 has set for third party applications. Apps are no longer allowed to query or check other running apps whether it may be the installed files or the running processes.

The security that we can provide to our customers using for the iOS customers is that the Mobile Security for iOS has a feature called Safe Surfingthat can provide security to your device and at the same time protect you from malicious activities.
Safe Surfing is a secured browser that filters and provides protection against unsafe and unwanted websites. With Safe Surfing, you can do the following:

Browse the internet with peace of mind.

Stay safe before visiting websites by Scanning a Webpage in Safari Web Browser.

Check the safety of the website by Scanning a URL before navigating to it.

If in case that your phone is already infected with a malware or virus, here are the things that you should do:

1. Check the applications installed on your device and make sure everything is up to date. 2. Clear history and website data.3. Restore your device to its factory setting.